The model-free minimisation is now checking for multiple vectors per spin, and raises a RelaxError.
This is in response to James Nyirenda's <jamesn7414 att yahoo dott com> post at
https://mail.gna.org/public/relax-users/2012-05/msg00023.html (Message-id:
<1337916876.99384.YahooMailNeo@...>).
The RelaxMultiVectorError has been modified to accept a spin ID. This error is now raised if
multiple vectors exist per spin, as model-free analysis cannot handle this.
